1. Field of the Invention
The present invention relates to electrical generators and, more specifically, to an electrical generator that employs a piezoelectric semiconducting structure to convert mechanical energy into electrical energy.
2. Description of the Prior Art
A Schottky barrier is a metal-semiconductor junction that rectifies current and, thus, may be used as a diode. A metal-semiconductor junction that does not rectify current is called an Ohmic contact. The rectifying properties of a metal-semiconductor junction depend on the metal's work function, the band gap of the intrinsic semiconductor, and the type and concentration of dopants in the semiconductor.
A piezoelectric material is one that forms an electrical potential difference between two regions of the material when the material is subjected to uneven mechanical forces. For example, when certain piezoelectric materials are bent, they develop a positive voltage in one region and a negative voltage in another region.
Many micro-scale and nano-scale machines have been proposed for such uses as in vitro medical devices. However, most of these machines are limited by the size of the power source that drives them. Specifically, many such designs rely on chemical batteries to supply electrical power to the devices. Therefore, they can be no smaller than the battery used and are useful only so long as the battery is able to provide power.
However, some of such devices need to be operational for long periods, rather than be limited by the lifespan of a battery. Also, it may be extremely difficult to change the batteries in some devices, such as environmental sensors.
Therefore, there is a need for electrical generators that are capable of providing power for long periods and that are driven by environmentally-available mechanical energy.